IS31AP2112-ZLS2-TR

Overview

The IS31AP2112-ZLS2-TR is a high-efficiency stereo Class-D audio amplifier manufactured by Lumissil Microsystems. It operates from a single supply voltage of 4.5V to 26V for the loudspeaker driver, with an internal 5V regulator for analog circuits. The device delivers up to 20W per channel into an 8Ω load at 24V and supports parallel BTL mono operation delivering 40W into 4Ω. Key electrical characteristics include a quiescent current of 35mA, shutdown current under 25µA, and a typical efficiency of 88%. It features differential inputs, four selectable fixed gain settings (20dB, 26dB, 32dB, 36dB), and spread spectrum functionality to optimize EMI performance.

Feature Summary

• Adjustable power limit function allows users to set a voltage rail lower than half of 5V to limit speaker current and prevent damage.
• Output DC detection circuit protects speakers from long-time current stress caused by input capacitor defects or shorted inputs.
• Spread spectrum function is integrated to improve electromagnetic interference (EMI) performance during operation.
• Built-in protection mechanisms include short-circuit protection with auto-recovery options, over-temperature protection, and under-voltage detection.

Applications

• TV audio systems
• Boom-boxes
• Powered speakers
• Computer monitors
• Consumer audio equipment

Procurement Notes

Verify that the ordering suffix ZLS2 corresponds to the eTSSOP-28 package and tape-and-reel quantity of 2500 units as specified in the datasheet. Confirm the component meets industrial temperature range requirements (-40°C to +85°C). Ensure compatibility with lead-free assembly processes and check for any specific handling instructions regarding the exposed thermal pad soldering.

Selection Notes

Select this amplifier when a high-efficiency Class-D solution is required for stereo or mono applications without external heat sinks. It is suitable for designs needing differential inputs and configurable gain levels. Consider the built-in protections and power limit features for robust speaker management. Verify that the supply voltage range of 4.5V to 26V aligns with the system power architecture.

Part Context

The IS31AP2112 belongs to Lumissil Microsystems' line of high-efficiency Class-D audio amplifiers. It is designed to replace traditional linear or less efficient Class-D amplifiers in portable and stationary audio devices. The device integrates advanced audio processing capabilities and protection circuits, making it a comprehensive solution for modern consumer electronics requiring high output power in a compact form factor.

Replacement Considerations

Check for direct pin-to-pin replacements within the same manufacturer's portfolio that offer similar power ratings and package types. Verify if alternative components support the same differential input configuration and gain settings. Ensure that any substitute part maintains comparable EMI performance and protection feature sets.

FAQ

How is the short-circuit protection auto-recovery enabled?

Auto-recovery is enabled by connecting the FAULTB pin directly to the SDB pin. In this configuration, the latch state releases after 420ms, allowing the amplifier to attempt recovery if the overload persists.

What is the purpose of the PLIMIT pin?

The PLIMIT pin allows users to adjust the power limit level by setting a voltage divider from VDD to ground. This limits the peak-to-peak output voltage to protect speakers from excessive current stress.

How does the device handle DC detection faults?

If the differential outputs exceed determined voltage thresholds for more than 420ms, the DC detect error occurs. The amplifier enters a Hi-Z state, and the fault must be cleared by cycling the VCC supply, not by toggling the SDB pin.